Some tests with Xilinx DMA benchmark

1 files changed, 76 insertions, 8 deletions

diff --git a/apps/xilinx.c b/apps/xilinx.c
index 1312663..1ec31d7 100644
--- a/apps/xilinx.c
+++ b/apps/xilinx.c
@@ -1,8 +1,11 @@
 #define _BSD_SOURCE
+#define _POSIX_C_SOURCE 199309L
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdarg.h>
+#include <time.h>
+#include <sched.h>
 #include <sys/time.h>
 
 #include "pcilib.h"
@@ -14,9 +17,17 @@
 #define USE PCILIB_KMEM_USE(PCILIB_KMEM_USE_USER, 1)
 #define BUFFERS 16
 #define ITERATIONS 16384
-#define PAGE_SIZE 4096
+#define PAGE_SIZE 4096	// other values are not supported in the kernel
 #define TIMEOUT 100000
 
+/* IRQs are slow for some reason. REALTIME mode is slower. Adding delays does not really help,
+otherall we have only 3 checks in average. Check ready seems to be not needed and adds quite 
+much extra time */
+//#define USE_IRQ
+//#define CHECK_READY
+//#define REALTIME
+//#define ADD_DELAYS
+
 //#define WR(addr, value) { val = value; pcilib_write(pci, BAR, addr, sizeof(val), &val); }
 //#define RD(addr, value) { pcilib_read(pci, BAR, addr, sizeof(val), &val); value = val; }
 #define WR(addr, value) { *(uint32_t*)(bar + addr) = value; }
@@ -33,6 +44,23 @@ static void fail(const char *msg, ...) {
     exit(-1);
 }
 
+void hpsleep(size_t ns) {
+    struct timespec wait, tv;
+
+    clock_gettime(CLOCK_REALTIME, &wait);
+
+    wait.tv_nsec += ns;
+    if (wait.tv_nsec > 999999999) {
+	wait.tv_sec += 1;
+	wait.tv_nsec = 1000000000 - wait.tv_nsec;
+    }
+
+    do {
+	clock_gettime(CLOCK_REALTIME, &tv);
+    } while ((wait.tv_sec > tv.tv_sec)||((wait.tv_sec == tv.tv_sec)&&(wait.tv_nsec > tv.tv_nsec)));
+}
+
+
 int main() {
     int err;
     int i, j;
@@ -42,9 +70,25 @@ int main() {
     struct timeval start, end;
     size_t size, run_time;
     void* volatile bar;
+    uintptr_t bus_addr[BUFFERS];
 
     pcilib_kmem_flags_t clean_flags = PCILIB_KMEM_FLAG_HARDWARE|PCILIB_KMEM_FLAG_PERSISTENT|PCILIB_KMEM_FLAG_EXCLUSIVE;
 
+#ifdef ADD_DELAYS
+    long rpt = 0, rpt2 = 0;
+    size_t best_time;
+    best_time = 1000000000L * PAGE_SIZE / (4L * 1024 * 1024 * 1024);
+#endif /* ADD_DELAYS */
+
+#ifdef REALTIME
+    pid_t pid;
+    struct sched_param sched = {0};
+
+    pid = getpid();
+    sched.sched_priority = sched_get_priority_min(SCHED_FIFO);
+    if (sched_setscheduler(pid, SCHED_FIFO, &sched))
+	printf("Warning: not able to get real-time priority\n");
+#endif /* REALTIME */
 
     pci = pcilib_open(DEVICE, PCILIB_MODEL_DETECT);
     if (!pci) fail("pcilib_open");
@@ -70,30 +114,50 @@ int main() {
     WR(0x04, 0)
     
     WR(0x0C, 0x20)
-    WR(0x10, 0x20)
+    WR(0x10, (PAGE_SIZE / 0x80))
     WR(0x14, 0x13131313)
 
+    for (j = 0; j < BUFFERS; j++ ) {
+        bus_addr[j] = pcilib_kmem_get_block_ba(pci, kbuf, j);
+    }
 
     gettimeofday(&start, NULL);
+
     for (i = 0; i < ITERATIONS; i++) {
 	for (j = 0; j < BUFFERS; j++ ) {
-	    uintptr_t ba = pcilib_kmem_get_block_ba(pci, kbuf, j);
-	    WR(0x08, ba)
-	    
+//	    uintptr_t ba = pcilib_kmem_get_block_ba(pci, kbuf, j);
+//	    WR(0x08, ba)
+	    WR(0x08, bus_addr[j]);
 	    WR(0x04, 0x01)
 
+#ifdef USE_IRQ
 	    err = pcilib_wait_irq(pci, PCILIB_IRQ_SOURCE_DEFAULT, TIMEOUT, NULL);
 	    if (err) printf("Timeout waiting for IRQ, err: %i\n", err);
-	    
+
 	    RD(0x04, status);
 	    if ((status&0xFFFF) != 0x101) printf("Invalid status %x\n", status);
 //	    WR(0x04, 0x00);
+#else /* USE_IRQ */
+# ifdef ADD_DELAYS
+//	    hpsleep(best_time);
+	    do {
+		rpt++;
+		RD(0x04, status);
+	    } while (status != 0x101);
+# else /* ADD_DELAYS */
+	    do {
+		RD(0x04, status);
+	    } while (status != 0x101);
+# endif /* ADD_DELAYS */
+#endif /* USE_IRQ */
 
 	    WR(0x00, 1)
+#ifdef CHECK_READY
 	    do {
+		rpt2++;
 		RD(0x04, status);
 	    } while (status != 0);
-//	    usleep(1);
+#endif /* CHECK_READY */
 	    WR(0x00, 0)
 	}
     }
@@ -105,7 +169,11 @@ int main() {
     pcilib_close(pci);
 
     run_time = (end.tv_sec - start.tv_sec) * 1000000 + (end.tv_usec - start.tv_usec);
-    size = ITERATIONS * BUFFERS * PAGE_SIZE;
+    size = (long long int)ITERATIONS * BUFFERS * PAGE_SIZE;
 
     printf("%.3lf GB/s: transfered %zu bytes in %zu us using %u buffers\n", 1000000. * size / run_time / 1024 / 1024 / 1024, size, run_time, BUFFERS);
+
+# ifdef ADD_DELAYS
+    printf("Repeats: %lf, %lf\n",1. * rpt / (ITERATIONS * BUFFERS), 1. * rpt2 / (ITERATIONS * BUFFERS));
+#endif /* USE_IRQ */	    
 }